Method and apparatus for protective encapsulation of structural members subjected to tidal influence

ABSTRACT

A method and composition of matter for the encapsulation of the upper portion of a piling and header associated with a wharf, pier or the like, whereby this upper portion of the piling and header, while normally above the high tide mark, is often subjected to submergence due to climatic conditions and requires encapsulation by the composition of matter disclosed herein to prevent attack from marine microorganisms or marine borers.

RELATED APPLICATIONS

[0001] Applicant claims the benefit of provisional application SerialNo. 60/447,670, filed Feb. 19, 2003.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] This invention relates generally to a field of encasement orencapsulation of structural members, and more particularly to theencasement or encapsulation of structural members subject to submergencein either fresh water or salt water.

[0004] 2. Description of the Prior Art

[0005] The use of piles or piers as structural supports for wharfs,bridges, and other marine environment structures is well known. Theusual materials of construction for such marine structures are concrete,steel, wood or a combination or composite of the two or more of thesematerials. All of the aforementioned materials of construction arevulnerable to deterioration. In particular, wooden pilings have beenused for many years to support piers, wharfs, boat slips, and in someinstances, older bridges. It is well known that such pilings are subjectto may hazards necessitating the replacement of same. One major sourceof damage which drastically shortens the life expectancy of wood pilingis the attack on the piling by certain marine parasites andmicroorganisms. These marine microorganisms feed upon the cellulosematerial of the wood piling, extracting a food substance of apolysaccharide carbohydrate nature.

[0006] Particular marine microoganisms known to attack wooden pilingsinclude limnoria, gribbles, and teredo microorganisms. The teredo beginslife as a larva and begins its metamorphosis into an adult when it hasattached itself to the surface of a piece of submerged timber. Theteredo will begin burrowing into the submerged timber and its tailappendage will seal off the entry way. The only visible presence of ateredo is the occurrence of two microscopic siphon tubes, one for theinhalation of fresh water, and the other for exhalation. In its boring,the teredo will dispose of waste through the exhalation siphon and theinhalation siphon is designed to produce continuously circulating waterover the teredo's gills for the absorption of oxygen. New larva is alsodisposed of through the exhalation siphon to infest the same submergedtimber, or other timber. The specific danger with the teredo is that thesubmerged timber pile appears to be secure and in tack, when in fact,the interior of the pile may contain a great deal of infestation, thusweakening the pile.

[0007] The second marine bore, of the limnoria species, which issometimes referred to as a gribble, resembles lice and is about the sizeof a small ant, and it is capable of boring holes of approximately threemillimeters in diameter. The limnoria rarely penetrates the timber formore than ten to twelve millimeters, but they normally infest in greatnumbers on the outer layer of the submerged timber, such that thesubmerged timber takes on a honeycombed appearance with tiny individualchannels. This attack, combined with the eroding affects of the sea'stide, will break down the surface of the wood and expose new surfacesfor attack.

[0008] Previous efforts to safeguard these hazards include theimpregnation of the structures and/or the coating of the surfaces withspecial preservatives and protective coatings, using materials such ascreosote, tar, and impervious paints. While these materials do covercertain hazards, they are ineffective with respect to others, and thechemical treatments are subject to leeching, scaling and erosion byaction of the constantly moving surrounding water, taken together withthe temperature changes and shock forces. Further the high solidity andother constituents of sea water also contribute to degradation of theseprotective measures.

[0009] Applicant is the holder of U.S. Pat. Nos. 5,829,920 and 5,919,004directed towards an apparatus and method to form a combination of wrapand marine acceptable filler composite which can be pumped within thewrap in aerosol form which solidifies to fill the gap between the wrapand the piling, and also to fill any gaps in the piling caused by theaforementioned marine borers. The subject matter of Applicant's twopatents directed to those portions of the pilings that are constantlyunder water, and those portions of the pilings that are temporarilyunder water during normal high tide.

[0010] There is however a need to protect the upper portion of a pilingwhere it contacts the header of a pier or wharf, which area whilenormally not under water, may be subject to being under water duringvery high tides or flooding. Applicant's invention is directed to amethod of impregnating this portion of the piling and header to preventinfestation by marine borers.

OBJECTS OF THE INVENTION

[0011] An object of the present invention is to provide for a novelmethod and apparatus for encasement or encapsulation of a portion of apiling and header of a wharf which may be subjected to infrequentsubmergence.

[0012] Another object of the present invention is to provide for a novelmethod and apparatus for the encasement or encapsulation of a portion ofa piling and header of a wharf which can be installed in situ.

[0013] A still further object of the present invention is to provide fora novel method and apparatus for the encasement and encapsulation of aportion of a piling and the header of a wharf which is efficacious inprotecting as well as preventing further infestation and weakening ofthe timber.

SUMMARY OF THE INVENTION

[0014] A method and composition of matter for the encapsulation of theupper portion of a piling and header associated with a wharf, pier orthe like, whereby this upper portion of the piling and header, whilenormally above the high tide mark, is often subjected to submergence dueto climatic conditions and requires encapsulation by the composition ofmatter disclosed herein to prevent attack from marine microorganisms ormarine borers.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] These and other objects of the present invention will becomeapparent, particularly when taken in light of the followingillustrations wherein:

[0016]FIG. 1 is a side view of an unprotected piling subjected to marinemicroorganisms; and

[0017]FIG. 2 is a side view of Applicant's protective apparatus aspreviously patented.

DETAILED DESCRIPTION OF THE INVENTION

[0018]FIG. 1 illustrates a side view of a typical piling in positionwhich has suffered the infestation of marine microorganisms and marineborers. The typical pile 10 has been driven into the silt or sandybottom 11 of an ocean or salt water estuary or fresh water estuary to asufficient depth to provide stability in a pier, bulkhead or otherstructure 14 that has been constructed on top of the piling 10. Thepiling 10 comprises a normally generally cylindrical member which issubject to attack from the ambient atmosphere above the high water point16 and the action of the tide of the salt water ocean or estuary belowhigh tide point 16. It is in this area below the high tide mark 16 whichsuffers the most from the infestation attack of microorganisms or marineborers. In FIG. 1 there is illustrated a typical attack from themicroorganism or marine borer limnoria, which attacks the submergedportion of the timber or wood pile 10 in great numbers and causes thehoney comb or hour glass effect, which is not normally visible to theobserver above the surface of the water. This attack can reduce thesupporting strength of the wood or timber pile by as much as 15 percentper year if gone untreated. In this particular infestation attack, itcan be seen that the piling has undergone severe deterioration 20proximate to its lower end to the extend that such pier or structurewhich the pile is supporting is in danger.

[0019] While the result of the infestation illustrated in FIG. 1 isshown proximate to the silt or sandy base 11, the infestation andresultant weakening of the piling could occur any where along thelongitudinal axis of the piling that is repetitively positioned belowthe high tide mark 16. The Applicant has addressed this issue withrespect to U.S. Pat. Nos. 5,829,920 and 5,919,004 which teach a methodand apparatus for wrapping the piling and encapsulating it with a marinegrade foam (see FIG. 2). However, there remains a minor problem whichhas still not been addressed properly. This is the area of the piling 10proximate the header 22 which supports the pier, wharf or the like. Thisarea is not normally subjected to submergence since the high tide markis generally below this level. However, in certain circumstances, highflooding, ice jams and the like this area of the upper piling 10 andheader 22 can be subject to submergence and thus the attack ofmicroorganisms or marine borers. One way to address the problem would beto install the wrap as disclosed in the aforesaid patents to as high apoint as possible on the piling. However, this solution does not protectthe wooden or timber header which supports the pier or wharf. The moreeffective solution is to treat the upper portion of the piling 10 andwooden header 22 with a composition of matter.

[0020] The composition of matter comprises a 100% solids, spray applied,aromatic polyurea coating which exhibits extraordinary toughness andelastomeric performance characteristics. It is applied in thicknesses offrom 30-250 mils or greater using multiple passes. It is seamless,abrasive resistant, and water proof and can be applied in situ.

[0021] In the preferred embodiment, the composition of matter used totreat the upper portion of the piling and header is a foam comprising amixture of isocyanate, up to 20 percent by weight, CHCIF₂, up to 2percent by weight of water, and a combination of polyols having anaverage OH number of from about 300 to 500 and comprisingpolyalkoxylated glycerine having an OH number of from about 200 to about300 in which the alkoxy groups each have from two to about three carbonatoms.

[0022] While the present invention has been described with respect tothe exemplary embodiments thereof, it will be recognized by those ofordinary skill in the art that many modifications or changes can beachieved without departing from the spirit and scope of the invention.Therefore it is manifestly intended that the invention be limited onlyby the scope of the claims and the equivalence thereof.

I claim:
 1. A process for creating a controlled environment andencapsulation of the upper portion of a piling and associated headernormally positioned about the high water mark, but subjected tointermittent flooding and therefore attack from marine infestation,comprising the steps of: a. encapsulating the upper portion of thepiling and associated header with a spray foam in a thickness of from 30to 250 mils, said foam comprising a mixture of isocyanate, up to about20 percent by weight CHCIF₂, up to about 2 percent by weight of waterand a combination of polyols having an average OH number of from about300 to 500 and comprising polyalkoxylated glycerine having an OH numberof from about 200 to about 300 in which the alkoxy groups each have from2 to about 3 carbon atoms; b. allowing the spray foam to set; and c.performing the aforesaid steps when the water level is below its highwater level.
 2. The process in accordance with claim 1 wherein saidprocess if performed on said upper portion of said piling and saidassociated header after said submerged portion of said piling has beensuitably jacketed and said jacket has been injected with the foam of thepresent invention in accordance with the teachings of U.S. Pat. Nos.5,919,004 or 5,829,920.